Odor has long been a challenge with absorbent articles such as diapers, adult incontinent products, feminine hygiene products, as well as bandages, wound dressings, and other such items. These articles are designed to contain body or physiological waste materials, which generally take the form of fluids (such as blood, urine, perspiration, etc.). There are odors associated with these waste materials, such as due to microbial activity (on urea in urine, on protein and lipids in blood, etc.) and so forth, and there have been many attempts to reduce or eliminate such odors. Such attempts generally fall into one of three categories. One is the use of added materials to absorb or adsorb volatile odors in an effort to restrict their release to the surrounding environment. Another is the use of masking materials such as perfumes. A third is the use of substances to inhibit the production of bodily fluid degradation products.
Many absorbent articles are configured to include a fluid absorbent core disposed between a top sheet and a back sheet. The top sheet is typically formed from a fluid-permeable material adapted to promote fluid transfer into the absorbent core, such as upon a fluid insult, usually with minimal fluid retention by the top sheet. Accordingly the top sheet material may be hydrophobic. The absorbent core is adapted to retain fluid, and the back sheet is typically formed from a fluid-impermeable material to form a barrier to prevent retained fluid from escaping. The absorbent core may consist of one or more layers, such as layers to acquire, distribute, and/or store fluid. In many cases, a matrix of cellulose fibers, such as in the form of an airlaid pad and/or non-woven web, is used in (or as) the absorbent core of absorbent articles. In some cases, the different layers may consist of one or more different types of cellulose fibers, such as cross-linked cellulose fibers. The absorbent core may also include one or more fluid retention agents, such as a superabsorbent polymer, distributed throughout the fiber matrix.
Whatever the structure, there continues to be a need for effective odor control in a wide range of absorbent articles. A robust odor control system would not only eliminate odors present at the time of fluid insult, but also arrest the generation of subsequent odors.